Electric transmitter suitable for use in automatic telegraphy



ug 1930- R. D. SALMON 3. 3

ELECTRIC TRANSMITTER SUITABLE FOR USE IN AUTOMATIC TELEGRKPHY Filed Feb.24, 1928 3Shees-Sheet 1 Aug. 26, 1930. v R. D. SALMON 1,773,865 ELECTRICT RANSMI TTER SUITABLE FOR USE IN Au'romA'rIq TELEGRAPH! Filed Feb. 24,1928 s Sheets-Sheet 2.

Aug. 26, 1930. v D. SALMON 1,773,866-

ELEQTRIC, TRANSMITTER SUITABLE FDR USE IN AUTOMATIC TELEGRAPHYv FiledFeb. 24, 1928 3 Sheets-Sheet '34 Patented Aug. 26, 1930' NI ED- STATESPATENT oFFics-j REGINALD DENNIS SALMON, or CROKYYDONJENGLAND', ASSIGNOR,BY .MEsnn-AssreN MENTS, TocR En ANDCOMPANY LIMITED/0E onoynon, ENGLANDELECTRIC 'rnAnsMIT'rERsUI'rABLE FOR USE IN AUroMn'rro 'rEnEGRAPHY i 1Application filed February 24, 1928. Serial No. 256,792, and, in GreatBritain March 7, 927.

Thisinvention relates toel ectric transmitters of the kindsuitable foru'seFinautoinatic telegraphy, and which. are controlled either by tape'punchedto accord with a multiple unit system, or by a keyboard, andwhich is adapted totransmit signals for controlling,

at a distance therefrom, printing or other receiving mechanism, eitherof the start-stop, or continuously running type. The invention relatesparticularly to that type of such electric transmitters in which asingle switch contactismovable into and out of engage.

ment with but a single pair of stationary positiveiand negative'contactsand is controlled,

' as to position, successively in respect'of. each signal unit, theswitch movements being due I to the motor operation of a series of camdevices, acting in. cyclic order, upon members the movements of whichmay or may not be transmitted to the movable switch member, inaccordance with the condition of the punched tape presented to; a seriesof peckers under the control ofthe cam or other-devices and the tape, orto the relative position of a series of combination bars under thecontrol of a. V keyboard.

In; electric transmitters of the kind re-. ferred to, controlledbyg-punched, tape, thev movable switch contact haszbeen positivelyconnected to. actuating means, such for 'instance as a spring controlledpivoted plate, subject tothe movementof levers that are under the jointcontrol of'the the series of cam devices, the peckers and punched tape,

the movable switch contact being normally held against one of thestationary contacts,

usually the .negativecontact, by the spring controlled; plate, when thelevers and peckersv are in their. inoperative position. but being movedinto contact with the opposite stationary contact, by one or other ofthe pecker 7 controlled levers,'acted upon by a spring of greaterstrength than that of the spring associated with: the 'movable' contactactuating plate, whenever the'corresponding pecker is enabled to enterahole in the associated punched tape. v w y 'The'present invention hasreference to improvements in electric transmitters of Y the kind abovereferred toyzindithas for its 0b-.

'more clearly defined than usual.

j ect to improve the construction and. operation of such apparatus andin particular 'toenable the movable contact of the switch device to actina quicker manner and" make more effective contact with the.stationary,

contacts than heretofore, so that the signals transmitted thereby shallbe stronger and For this purpose, the movable switchcon I tact arrangedbetween the positive and nega tive stationary contactsof the switchClGVlCG, instead of being fixed to the spring controlled actuatingmeansfis mounted independently of such spring controlled means butadapted to .beinovedin each direction bysuch actu ating means under thecont-rol'ofperforated l tape or combination bars, a and to be heldagainst the contact towards which it has-been moved, :with the minimumof bouncing or rebounding, by the action thereon of an inde-.

tact partly from one stationary contact towardjthe otherstationarynontact and thatv so i when the'movable contact has justpassedits. 7 mid position; the, spring controlled .antibounce device willcomeinto actionto com I plete the movement of the movable "contact andhold such contact firmly against the" stationary contact towardshwhichit. was first moved by. thev spring eon-trolled actuated means. In thiscase, independent;

.me'ans, 'such as stops, maybe provided to limitjthe movement.OfJtllQQSPIlIIg con 70 Y I pendent springiactuated device hereinafter Hcalled for. distinction the antirbounce device. The arrangement may. besuch that the-said the transmitter rendered capable of actingefiiciently at a higher speed than before and the movable contact iscaused to act practically in a dead-beat manner.

A switch having a movable contact and actuating means therefore, adaptedto act in either of the ways set forth, can be variously modified and beembodied in various constructions of electric transmitters of the kindreferred to.

In the accompanying illustrative drawings, Fig. 1 shows in frontelevation and Fig. 2 in rear elevation with part broken away, oneconstruction of electric transmitter according to the invention. Fig. 3is a section on the line III-III of Fig. 1. Fig. 4 is a front elevation,to a larger scale, of the contact block shown in Fig. 1. Fig. 5 is aplan view of the pecker levers and peckers shown in Fig. 1. Figs. 6 and7 are detail views to an enlarged scale, showing a spring controlledplate for moving the movable contact first in one direction and then inthe other.

In the example shown in Figs. 1 to 5, 1 is the movable contact arrangedbetween the stationary contacts 2 and 3 of the switch device and carriedby a metal arm or blade 4 pivoted at one end at 4 to a plate 5 fixed toa block 5 of insulating material to which the contacts 2 and 3 are alsofixed. The tape controlled actuating means is a spring controlled plate6 pivoted at 7 and similar in function to that used in known electrictransmitters of the type referred to, but such plate instead of carryingthe movable contact 1, as heretofore, is made of bifurcated shape andone of its arms is provided with a fork-like device 6 that looselyembraces the free end of the arm or blade 4 carrying the movablecontact 1. The anti-bounce device consists of a. separate springcontrolled jockey pulley or roller 8 adapted to act against the freeV-shaped end portion of the said arm or blade 4, or it may be upon asimilar shaped projection carried by some other part of the blade. Thejockey pulley in the example shown, is mounted on one side of an arm 8pivoted at 8 and connected to one end of a blade spring 8 the other endof which is fixed in position by an adjustable eccentric 8 9 is a coiledspring connected to the plate 6 and adapted to move the same in thedirection of the arrow w in Fig. 1 and cause the forklike device 6 tomove the blade 4 in a direction to cause the movable contact 1 to bearagainst the contact 3 and normally hold it in that position. Thearrangement is such that the spring controlled plate 6 can, under thecontrol of perforated tape and through the fork-like device 6*, move theblade 4 in either direction, to move the switch contact 1 from thestationary contact against which it is bearing, towards and against theopposite stationary contact, and that the spring controlled jockeypulley 8 will act to hold the movable contact against the saidstationary contact, with the minimum of bouncing or rebounding of thecontact. The fork-like device 6 (Figs. 1 and 6) may, when the springcontrolled plate 6 is moved in either direction, cause the contact 1 tomove from the contact 2 or 3 against which it is bearing, toward andagainst the opposite contact, the jockey pulley S acting to hold themovable contact firmly against the stationary contact toward and againstwhich it is moved by the fork-like device 6 and prevent bounce orrebound or the movable contact. .01" the forklike device 6 may, when thespring con trolled plate 6 is moved in either direction, act to move thecontact 1 from the contact 2 or 3 against which it is hearing, onlypartly towards the opposite contact and slightly past 1e centre of theocirey pulley 8 which afterwards acts to complete the motion of thecontact, independently of the plate 6, and hold the contact firmlyagainst the said opposite contact, with the minimum of bouncing of thecenter. In this case, stops 6 and 6 are provided, as shown in Fig. 7, tolimit the movement of the plate 6 in each direction.

In an arrangement of either of these kinds, the movable switch contact 1may be con nected to a telegraph line either directly, or, it may be,indirectly through a line relay in known way, and the two stationarycontacts 2 and 3 be connected to the positive and nega tive polesrespectively of a split battery 11 (Fig. 6) ti e middle point of whichis preferably adapted to be connected to earth in the usual known way,the movable contact 1 normally being held. by the means describedagainst one of the stationary contacts, it may be against the negativecontact 3.

The spring controlled plate 6 may be arrangedto be raised, against theaction of its spring 9, to cause the movable switch contact 1 to movefrom the stationary contact 3 against which it normally bears, to ortowards the other stationary contact 2, by the free end of one or otherof a series of separate spring controlled lever arms 12 arranged belowone of the arms of the bifurcated plate 6 and carrying the tape packers13, the lever arms 12 being pivoted at their other ends at 12, andarranged below a series of rotary cam devices 14 adapted to release thelever arms 12 in cyclic order and permit each of them to rise insuccession, under the action of 1..-

its spring 12*, if its pecker is then opposite a corresponding hole inthe tape, as in the construction of electric transmitter described inthe specification of an application for Letters Patent filed 16thAugust, 1926, Serial No. 129,440. 7

The invention can however advantageous ly be embodied in electrictransmitters of other knownor suitable kind of the type referred to, asfor instance those in which the pecker levers act indirectly upon aspring controlled'switch operating plate or lever v I the action of itsspring 9. l For'e'xample, as-

suming that the total lift of each pecker 13, as'controlled by its cam14, be divided-into five parts, then the pecker may be allowed to risethrough 'part of its upward travel before touching or entering the tape,and then through another th part of its upward travel, in the tapebefore its corresponding lever arm 12 touches the adjacent arm of thespringactuated plate 6, then'through another ths part of its travel inthe tape before causing the said plate to move'the movable switchcontact 1 from the negative switch contact to the positive switchcontact, the remaining th part of its possible travel, during the firstsmall portion of which the plate moves the contact 1 from thenegativecontact r 3 to the positive contact 2, being idle andtospare,'that is to say, it is arrested by the spring controlled platecoming to' rest on. the movable contact arm before it has completed itstotal possible movement as allowed by its cam 14. p

The series of rotary cam devices 14 used in the electric transmitter formoving the I pecker levers 12 downward against theaction of theirsprings 12* and afterwards releasing them, in cyclic order, mayadvantageously be constituted by the bottom of a series of annulargrooves cut in a sleeve 17 (Fig. 3) fixed to a driving shaft '18, thebottom of each groove having a portion thereof cut away to form a flatsurface on its periphery, the several flat surfaces being spaced apartangu larly around the sleeve. The collars between the grooves act asguides for the levers 12.

When the electric transmitter is designed to control start-stopprinting'mechanism, a

cam controlled lever 12 without a pecker is provided to causethe movableswitch contact 1 tobear against say the positive station- I ary contact2 to transmit a starting signal,

and an interval of time is arranged to be left I I between the operationof the-last lever 12 carrying a pecker 13 andthe lever 12 by suitablyadjusting the timing of the correresponding cam device 14, in order toleave the movable switch contact 1 for a sufiicient time against say thepositive contact 2, to send a stoppingsignal, as in the electrictranmitter described in the specification of the former application" forLetters Patent Serial No. 129,440 hereinbefore referred to.

may be I Or a caincontrolled lever without a pecker, arranged totransmit a stopping signal.

In the case where the movable switch mem-j.

ber is under the control of" a key board, the controlling means maybe ofthe kind described in the specification of a former application forLetters Patent Serial No. 1253, 141

filedv 16th August I 1926. d

What I claim is 5 p v 1. A telegraph transmitter comprising-a pairofstationary contacts, a movable contact arranged between and adapted toco-act I with the said stationarycontacts,'rneansto I hold the saidmovable contact firmly against either of'the said stationarycontacts,-a'nd' means to actuate the said movable contact from aplurality of cam and spring operated Y levers and controlledinaccordance with signals to be transmitted, consisting essentially of asingle member mounted independently of, but in operable relation"with,the said movable contact. g

2. A telegraph transmitter comprising a pair of stationary contacts, a;movable switch contact arranged between the said stationary contacts,"independent means to hold the saidniovable contact withtheminimumofbounc-' ing against the stationarycontact toward which it has beenmoved,'and means to actuate the said movable contact in accordance withsignals to be transmitted, comprisingqa plurality of cam and springoperated levers co operatingwith a single member which is in operablerelation with the said movable contact during aportion only of themovement thereof.

3. A telegraph transmitter comprising a pair of stationary contacts, amovable switch contact arranged between the said stationary contacts, aplurality of cam and spring operated. levers" operating. successivelyand individually according to signals to be trans- 1 mitted, a springcontrolled'plate responsive to tlie movement of the said levers andcarrying abutments adapted to engage with the said movable switchcontact during a portion only of its movement, and independent means tocomplete the movement'ofthe said movable switch contact and to hold itfirmly against the. stationary. contact. towards whichit-has been moved.

A telegraph transmitter comprising a pa r of stationary contacts,'amovable switch contact arranged between the saidstationary contacts, aplurality of cam and springop-- erated levers operating"successively andindlvldually and controlled in accordance'with signals to betransmitted, a springcontrolled plate responslve to the movement of anyone ofthe' said levers, and carrying a fork-like device loosely.embracingthe end of the said '7 movable switch contact andadapted to ensgage the same near theextreme positions of the said fork-likedevice,stops to limit the motion of the said fork-like device, and independentmeans to complete the movement of the said movable switch contact and tohold it firmly against the contact towards which it has been moved.

5. A telegraph transmitter comprising a pair of stationary contacts, amovable switch contact arranged between the said stationary contacts, aplurality of cam and spring operated levers operating successively andindividually according to signals to be transmitted, a spring controlledplate responsive to the movement of the said levers and carrying aforkdike device loosely embii-vcing the end of the said movable switchcontact and adapted to move the same for a portion only of its travelfrom one stationary contact to the other, and independent springcontrolled means to complete the movement of the said movable switchcontact and to hold it firmly against the stationary contact towardswhich it has been moved.

6. A telegraph transmitter compr'sing a pair of stationary contacts, amovable switch contact arranged between the said stationary contacts, aplurality of cam and sprin operated levers operating successively andindividually and controlled in accordance with signals to betransmitted, a spring controlled plate responsive to the movement of anyone of the said levers and carrying a fork-like device loosely embracingthe end of the said movable switch contact and adapted to engage thesame near the extreme positions of the said fork like device, stops tolimit the motion of the said fork-like device and a spring controlledjockey roller adapted to act against the free end of the said movableswitch contact and to hold the same firmly against the stationarycontact towards which it has been moved.

7. A telegraph transmitter comprising a pair of stationarycontacts, amovable switch contact arranged between thesaid stationary contacts, aplurality of cam and spring operated levers operating successively andindividually according to signals to be transmitted, a spring controlledplate responsive to the movement of the said levers and carrying afork-like device loosely embracing the end of the said movable. switchcontact and adapted to move the same for a portion only of its travelfrom one stationary contact to the other, and a spring controlled ockeyroller adapted to act against the free end of the said movable switchcontact to complete the movement of the same and to hold it firmly witha minimum of bouncing against the stationary contact towards which ithas been moved.

8. A telegraph transmitter for transmitting signals previously recordedas perform tions in a tape, comprising horizontal levers pivoted at oneend, peckers pivoted near the other ends of the said levers, came meansacting directly on the said levers intermediate the pivoted ends and thepeclzers to release the said levers successively for movement, a memberhaving one portion extending horizontally over all the said levers atthe ends nearest the said peckers and another portion at an angle to thefirst mentioned portion but in substantially the same vertical plane andcarrying a forl lil e device loosely embracing the end of a movablecontact, stationary contacts between which the said movable contactoperates, and means for holding the said movable contact against thecontact to which it was last moved.

Signed at London, England, this 14th day of February, 1928.

REGINALD DENNIS SALMON.

